Pathology and biology guidelines for resectable and unresectable neuroblastic tumors and bone marrow examination guidelines.

The recommendations concerning tumor and bone marrow handling for the evaluation of molecular-biologic and molecular-genetic and immunologic markers presented in this paper were developed by the SIOP Europe Neuroblastoma Pathology and Biology and Bone Marrow Group. Although the Guidelines were developed for neuroblastic tumors (neuroblastoma, ganglioneuroblastoma and ganglioneuroma), they are applicable to all other tumor entities as well. The paper is subdivided in three main parts. The Pathology Guidelines give an overview about the handling, sectioning and securing of tumor material in case of resectable and non-resectable neuroblastic tumors. The Guidelines encompass open biopsies, tru cut biopsies, fine needle aspirations, and bone marrow aspiration. The importance of the pathologic evaluation for the interpretation of the molecular-genetic and molecular-biologic results, which also includes the exact determination of the tumor cell content is stressed. Besides this, recommendations concerning tumor material obtained after cytotoxic therapy, immunohistologic and immuno-cytologic issues and lymph node examination are addressed. In the Biology Guidelines, the different methods for MYCN, chromosome 1p36 investigations and DNA content measurements are discussed and DNA probes are recommended. Furthermore, specified definitions and a common terminology already used in the SIOP Europe Neuroblastoma Group are presented. In the Bone Marrow Guidelines, recommendations concerning the methods to be employed are given and the most important pitfalls are demonstrated. Both the use of standardized methods and the application of a common language will, it is hoped, contribute to the quality and reliability of collected data and thus to a better comparability between and among research reports. These improvements should prove to be of great value for the affected patients.